As Britain decides whether to leave the E.U. in a historic first, that identity is at the forefront of many people's minds. And while a Dutch architect might seem like an odd advocate for a debate going on in the U.K., Koolhaas and the research wing of his firm, AMO, have been involved in establishing the idea of the E.U. for decades. "The whole idea to question it is really crazy," Koolhaas argued recently, as Building Design reports.

Back in 2001, after being invited to participate in brainstorming sessions about the capital of Europe, AMO famously proposed a visual language for the then-burgeoning E.U.. "AMO found Europe’s representations to be mute, limp, anti-modern and ineffective in an age dominated by mass media," the group writes. They developed a new flag in response: a barcode of colors representing each member country—whose radical approach to a conventional visual language ruffled many feathers (it was ultimately never adopted). Since then, AMO has been closely involved with goings-on within the E.U., playing the role of thoughtful antagonist in debates about its identity and politics.

So what does Koolhaas think of the Brexit vote? In a BBC radio interview recently, the architect argued that joining the European community in the 1970s helped England "[open] up itself, helping to modernize the whole of the English mentality—the whole of the English civilization." Leaving it, he continued, is an act of nostalgia-fueled obliviousness: "If you look at the arguments now to leave you can really see that this is a movement of people who fundamentally want to change England back into the way it was supposedly before," he said on the BBC, "so there is much more at stake than being simply in or out."

Koolhaas isn't the only architect making statements against Brexit. David Adjaye, Richard Rogers, Eyal Weizman, and David Chipperfield all signed a collective letter against Brexit recently, arguing that the creative industry has much to lose by leaving the E.U.

Indeed, it's easy to imagine how architects who work across Europe could be deeply affected by the exit of England, from making it more difficult to obtain work visas, to complicating the development of new projects. "The biggest risk to the profession is likely to come from economic uncertainty caused by a no vote," wrote Building Design editor Thomas Lane in an op-ed.

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